The event was attended by the 30-year-old actress's friends including Riteish Deshmukh, Genelia D'Souza among others.
"Genelia, Riteish at Dia's pre-wedding brunch!! Friends forever," Balaji CEO Tanuj Garg posted on Twitter along side a picture of the three.
Dia and Sahil's wedding will take place in Delhi and will be attended by the couple's family and close friends.
The pair will host a reception party in Mumbai later.